November 13, 2008

To Skip or Not to Skip

As you know, I have been HIV positive since the start of this epidemic so I have seen a lot of change since 1981. For the first five years, we had no anti-HIV medications.

In 1996, the world of HIV and AIDS changed with the release of potential life saving anti-HIV medications including protease inhibitors. But if you are taking medications, you know the downsides of side effects. So I have been asked many times if it is okay to skip doses.

First of all, there has been a few studies to see what happens when you stop medications or do not take them as directed. I even participated in one of these trial studies at the National Institute of Health in Bethesda, Maryland. I will be covering some of this today.

The technical term used for taking your HIV treatment properly is adherence. Good adherence to HIV treatment is essential to its success.

It has long been thought that the very minimum level of adherence needed for HIV treatment to have a good chance of success is 95%. That means missing no more than a dose or two of your treatment every month.

But this was based on quite old research involving people who were taking combinations of HIV drugs that included protease inhibitors that were not boosted by ritonavir and this type of HIV drug is not recommended any more.

Researchers conducting a recent study wanted to find out what level of adherence is needed for modern HIV treatment combinations (that include either an NNRTI or a ritonavir boosted protease inhibitor) to have the best chance of successes.

Levels of adherence in the study were high, and only 83 of the 1059 people in the study experienced an increase in their viral load to detectable levels. These people took about 76% of doses of their HIV treatment.

Compared to people who took at least 90% of their doses, there was a 9% risk of viral load increasing to detectable levels for people who took between 80 and 90% of their doses. There was almost a 50% risk of viral load becoming detectable for people who took between 70% to 80% of their doses, and an over 75% risk of this for people who took fewer than 70% of their doses.

But the researchers emphasize that people should aim to take all doses of their medication since very few people who took at least 90% of their doses experienced an increase in their viral load.

Treatment breaks

Breaks or ‘holidays’ from HIV treatment (or structured treatment interruptions) are not recommended.

This is because the largest HIV clinical trial ever conducted (the SMART study) found that people who stopped their HIV treatment when their CD4 cell count was around 350, restarting when it fell to around 200, had a higher risk of becoming ill with HIV related and some serious non HIV related illnesses as well compared to people who took their HIV treatment all the time.

But now Italian researchers have found that people with CD4 cell counts above 350 who took treatment breaks did just as well as people who took their treatment all the time.

The Italian study lasted four years and involved 329 people (that is important to note the SMART study involved over 5000 people). However, it had a different design to the SMART study since treatment was stopped at a much higher CD4 cell count (700), and was restarted when a person’s CD4 cell count fell to around 350, the level at which treatment was stopped in the SMART study and the now recommended level at which HIV treatment should be started.

Approximately 12% of people in the Italian study became seriously ill due to any cause, regardless of whether they took their treatment all the time or took a break from treatment.

The people who took breaks from their treatment needed to take a lot less HIV treatment since they were off treatment for an average of 75% of the time.

One of the most important findings of the SMART study was that treatment breaks increased the risk of some serious non HIV related illnesses, for example heart disease. The Italians, however, found that the rate of heart disease was lower for people who took treatment breaks.

Weekend breaks from treatment?

A separate piece of American research has found that people who take HIV treatment that includes efavirenz (Sustiva) with Truvada (FTC and tenofovir) may be able to take a break from their treatment at weekends.

It was a small, six-month study involving only 60 people who were divided into two groups with different instructions - to either take their treatment all the time, or to stop it at the weekend.

The first set of results showed that equal numbers of people (80%) in each group, kept their viral load undetectable, regardless of whether they took their treatment all the time or took a weekend break.

But a small number of people dropped out of the study, and when the researchers excluded them from their analysis, they found that all the people who took weekend breaks kept their viral load undetectable compared to 85% of those who their treatment all the time.

The researchers found that taking weekend breaks was popular with patient.

So what should all this mean to you? I can only talk from personal experience and I want to live as long as I can and as with as good a quality of life as I can have.